1. Field of the Invention
The present invention relates to a seat belt device for a vehicle, in particular, to one which can further facilitate fastening of a seat belt, which is mounted on the seat, when an occupant wears or takes off the seat belt.
2. Description of Related Art
A vehicle seat is generally provided with a seat belt (also called a safety belt) designed to encircle the chest and/or waist of an occupant in order to prevent the occupant from getting hurt in case of an accident. While various types of seat belts are used, the most common seat belt is equipped with a tongue made of metal, attached to a length of belt webbing, and a buckle head fixed to the seat, and is fastened by fitting the tongue into the buckle head and unfastened by separating the tongue from the buckle head.
Since the buckle head is connected to a piece of webbing attached to the seat, it may be caught under the seat or between seats, which would otherwise cause the use of the seat belt to be inconvenient.
Recently, in order to facilitate belt fastening while solving the foregoing problem, seat belt devices capable of displacing the buckle head have been introduced, Among these devices, a seat belt device having a displaceable buckle head, which can be displaced forward of the seat, is disclosed.
FIG. 1 is a side elevation view illustrating a seat belt apparatus including a conventional forwardly-displaceable buckle head.
As shown in FIG. 1, a buckle head 12 coupled to a carrier 13 is provided on the side of a seat S such that it can be displaced along a screw 15A, One end of the screw 15A is supported by a support member 16, and the other end of the screw 15A is connected to a motor 17 A such that the screw 15A can be rotated forward or backward by the motor 17 A .
Following the rotation of the screw 15A, the carrier 13 can move along the screw 15A, and the buckle head 12 coupled to the carrier 13 can be displaced forward or backward of the seat by the carrier 13.
When the occupant attempts to wear the seat belt, he/she couples a tongue 11 to the buckle head 12 by displacing the buckle head 12 to a position where the seat belt can be properly fastened according to his/her body.
However, the conventional buckle head 12 is displaceable only in the horizontal direction, i.e., forward and backward of the seat, fixed to the carrier 13. Accordingly, the vertical position of the buckle head 12 cannot be adjusted. Furthermore, if the coupling angle of the tongue 11 and the buckle head 12 is not properly set, this configuration may disadvantageously cause belt fastening to be rather inconvenient.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.